US Senate Democrats on Tuesday, for the second time in a week, blocked legislation meant to kill an Iran nuclear deal negotiated by the Obama administration and other world powers with Tehran.

With the voting continuing, there were 41 Democrats voting to block the measure to disapprove the Iran deal from advancing in the Senate, enough to deny Republicans the 60 votes they need in the 100-member Senate.

Senate Majority Leader Mitch McConnell staged the second vote in an attempt to lure at least a couple Democrats into voting for the resolution of disapproval.

McConnell also moved to arrange a third procedural Iran vote, possibly this week, on an amendment preventing Obama from lifting economic sanctions against Iran until that country’s government formally recognizes Israel’s right to exist and releases American citizens being held in Iranian custody.

It was not yet clear how Democratic votes would line up on that amendment.